A schematic of isobaric labeling: proteins are extracted from different conditions or cell types, digested into peptides, and labeled with isobaric stable isotope tags. These tags consist of reporter, balance, and reactive regions. Lighter reporter regions are paired with heavier balance regions, such that the entire tag attached to the peptide adds the same mass shift. Therefore, after mixing, in MS1, the peptides appear as a single precursor. However, when fragmented during MS2, in addition to the normal fragment ions, the reporter regions dissociate to produce ion signals which provide quantitative information regarding the relative amount of the peptide in the samples.
Isobaric labeling is a mass spectrometry strategy used in quantitative proteomics. Peptides or proteins are labeled with chemical groups that have (at least nominally) identical mass (isobaric), but vary in terms of distribution of heavy isotopes in their structure. These tags, commonly referred to as tandem mass tags, are designed so that the mass tag is cleaved at a specific linker region upon high-energy CID (HCD) during tandem mass spectrometry yielding reporter ions of different masses. The most common isobaric tags are amine-reactive tags.[1] However, tags that react with cysteine residues and carbonyl groups have also been described.[2] These amine-reactive groups go through N-hydroxysuccinimide (NHS) reactions, which are based around three types of functional groups.[2] Isobaric labeling methods include tandem mass tags (TMT), isobaric tags for relative and absolute quantification (iTRAQ), mass differential tags for absolute and relative quantification, and dimethyl labeling.[1] TMTs and iTRAQ methods are most common and developed of these methods.[1] Tandem mass tags have a mass reporter region, a cleavable linker region, a mass normalization region, and a protein reactive group and have the same total mass.[3]
^ abcBantscheff, Marcus; Lemeer, Simone; Savitski, Mikhail M.; Kuster, Bernhard (2012-09-01). "Quantitative mass spectrometry in proteomics: critical review update from 2007 to the present". Analytical and Bioanalytical Chemistry. 404 (4): 939–965. doi:10.1007/s00216-012-6203-4. ISSN 1618-2650. PMID 22772140. S2CID 21085313.
^ abYates, John (2014). "Isobaric Labeling-Based Relative Quantification in Shotgun Proteomics". Journal of Proteome Research. 13 (12): 5293–5309. doi:10.1021/pr500880b. PMC 4261935. PMID 25337643.
^Thompson, Andrew; Schäfer, Jürgen; Kuhn, Karsten; Kienle, Stefan; Schwarz, Josef; Schmidt, Günter; Neumann, Thomas; Hamon, Christian (2003). "Tandem Mass Tags: A Novel Quantification Strategy for Comparative Analysis of Complex Protein Mixtures by MS/MS". Analytical Chemistry. 75 (8): 1895–1904. doi:10.1021/ac0262560. ISSN 0003-2700. PMID 12713048. S2CID 30820837.
Isobariclabeling is a mass spectrometry strategy used in quantitative proteomics. Peptides or proteins are labeled with chemical groups that have (at...
affinity tags (ICAT), isobariclabeling (tandem mass tags (TMT) and isobaric tags for relative and absolute quantification (iTRAQ)), label-free quantification...
Isobaric tags for relative and absolute quantitation (iTRAQ) is an isobariclabeling method used in quantitative proteomics by tandem mass spectrometry...
core structure; TMTduplex, an isobaric pair of mass tags with a single isotopic substitution; TMTsixplex, an isobaric set of six mass tags with five...
in isotopic labeling may be stable nuclides or radionuclides. In the latter case, the labeling is called radiolabeling. In isotopic labeling, there are...
in the MS/MS spectra. Two commercially available isobaric tags are iTRAQ and TMT reagents. An isobaric tag for relative and absolute quantitation (iTRAQ)...
Stefan K.; Shortreed, Michael R.; Smith, Lloyd M. (2018). "Ultrafast Peptide Label-Free Quantification with FlashLFQ". Journal of Proteome Research. 17 (1):...
procedure is a chemical labeling based procedure that is performed in one step using amine-reactive isotopic reagents. The labeling of two samples uses either...
Electron-transfer dissociation Proteomics Quantitative proteomics and Isobariclabeling 2018, Discovery in Proteomic Sciences Award from the Human Proteome...
summit or nadir easy. Contour labels can be oriented so a reader is facing uphill when reading the label. Manual labeling of contour maps is a time-consuming...
In addition, the doubly-substituted isotopologues are often subject to isobaric interferences, as in the methane system where 13CH5+ and 12CH3D+ ions interfere...
density is 882.73 kgm−1. The isothermal compressibility is 674 TPa−1 and isobaric expansivity is 819 K−1. When bicyclohexyl is heated to around 427 °C (801 °F)...
idealization comprising the state space of possible states of a system, each labeled with a probability) that emphasizes properties of a large system as a whole...
topography on which altitudes (more precisely geopotentials) of the main isobaric surfaces (for example, 900, 800, and 700 millibars) counted off from sea...
spectrometry without prefractionation, although a discrimination between isobaric glycan structures is more challenging or even not always possible. Anyway...
Dow Chemical Company on their containment products. It is used in the labeling of biological materials that carry a significant health risk, including...
used to label and identify subcellular features of cells, such as immunogold labeling, can also be used with NanoSIMS analysis. Immunogold labeling uses...
spectrometry without prefractionation, although a discrimination between isobaric glycan structures is more challenging or even not always possible. Anyway...
spectrometry without prefractionation, although a discrimination between isobaric glycan structures is more challenging or even not always possible. Anyway...
Thus the set of all nuclides with the same A can be introduced; these isobaric nuclides may turn into each other via beta decay. For a given A there is...
points to the direction of maximum increase of p and is always normal to the isobar at that point. Since the flow packet feels a push from the higher to the...
being merged with its other creative agencies DentsuMB and Isobar under the Dentsu Creative label, effectively retiring the 360i brand. 360i started out as...
"tagged" with a label identifying the subset to which it belongs. Although the labeling may be quite arbitrary, temperature is just such a labeling process which...
there is a composite particle whose statistics label is not uniquely determined by the statistics labels of its components, but rather exists as a quantum...
protease activity. Formaldehyde or isobaric tags including Isotope-coded Affinity Tags (ICAT), 4 to 8 plex Isobaric tag for relative and absolute quantification...
Chemistry and Collisional Processes in Multipole Devices for Resolving Isobaric Interferences in ICP–MS. Jan 2000 - A Dynamic Reaction Cell for Inductively...
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